cm871 help---

[Bjswaste12]

background-- we have a cm871 450 hp 390k miles. driver came into our shop complained of low power. diagnosed to turbo not functioning properly. in sake of time, we replaced with a new turbo from peterbilt along with vgt controller. restarted truck, #6 injector code, replaced injector along with cam and 2 rockers(6 intake and 2 intake). the cam and rocker looked scarred when we removed the valve cover so we replaced while apart. truck restarted, idles fine with a bit of black smoke at idle. when the truck is revved up, occasional pop like a back fire, along with a tap sound and tons of smoke. checked egr, cleaned it. have not drove it after reassembly.